Optical circuit switches (OCSs) are the heart of optical circuit switching networks. An OCS includes a number of optical collimators (e.g., passive collimators), which direct optical signals into and out of optical fibers coupled to the OCS. Example performance characteristics of a fiber collimator include insertion loss, constancy of beam waist diameter, location of the beam waist relative to the center of the OCS optical path, and degree of random beam pointing error. The existing OCS collimators using etched silicon or polymer lens arrays may not meet the desired performance characteristics.